The present invention relates to a process for examining a loss of media of a motor vehicle as well as to a motor vehicle and to a system for implementing such a process.
It is a frequent occurrence that a motor vehicle loses oil while in traffic and leaves an oil slick on the road. Such contaminations of the road are particularly dangerous when the oil mixes with water and covers a wide area on the road as a thin film of oil. There are enterprises which specialize in the removal of such oil slicks. The oil slick can be rapidly and reliably removed by means of a wet cleaning method. However, this results in considerable cost. According to decisions of the German Federal Supreme Court (BGH VI ZR184/10 and VI ZR191/10 of Jun. 28, 2011), in Germany, a motor vehicle owner whose vehicle loses oil, is responsible for refunding the costs of a professional removal of the oil slick.
In addition to oil, motor vehicle may also lose other media. These are, for example, condensation water, gasoline, brake fluid. Condensation water presents no problem and requires no road treatment. When a car loses gasoline, as a rule, the road does not have to be treated because gasoline is very volatile and will evaporate rapidly. However, if it is determined that a motor vehicle is losing gasoline, the motor vehicle should immediately be taken to a repair shop, and the corresponding fuel lines should be examined and repaired. Otherwise, a gasoline gas—air mixture, which is explosive, can form at the motor vehicle.
Sometimes, motor vehicles also lose parts, for example, a portion of the exhaust or other mechanical elements. These parts should be removed from the road as fast as possible, and the corresponding vehicle should be repaired as soon as possible.
German patent document DE 25 20 014 A1 discloses a process for the detection of oil in fluids. In this case, an oil film can be detected optically or by means of electrodes.
In European patent document EP 1 327 875 A1, a process for the determination of oil concentrations in water is described. In this case, the oil concentration in underwater separation tanks is to be determined by means of light scattered in a measuring cell. The intensity of the Raman spectral line is measured, which correlates with the oil concentration in water.
In US 2014/0050355 A1, a computer process is described by means of which images of a film are examined for one or more blotches in the foreground, the patterns of the blotches being analyzed as to whether they represent surface oil.
A loss of media at a motor vehicle can also be detected by way of a level gauge. From German patent document DE 102 06 824 A1, for example, an optical level gauge is known for measuring the level in receptacles for fuel, washing water, oil, hydraulic fluid, etc.
In German patent document DE 10 2008 055 902 A1, a process is described for detecting a loss of oil in a transmission having a countershaft. A loss of oil is detected here by means of the course of the rotational speed of a countershaft of a transmission.
Furthermore, an oil aging sensor is indicated in European patent document EP 0 901 011 A2, by means of which the oil quality in a motor vehicle can be determined.
From U.S. Pat. No. 6,570,608 B1, a monitoring system is known by which a film (video) is analyzed and it is determined whether persons are entering a motor vehicle or are exiting a motor vehicle. In this case, differential images are produced in order to recognize the motor vehicles and the objects in front of the respective background.
US 2004/0161133 A1 discloses a method of monitoring and detecting unattended objects, such as luggage, vehicles or persons. The objects can be recognized according to predefined characteristics, such as their size or their type of movement. An alarm message will be emitted after a predefined time period.
A similar method for detecting left-behind objects is described in US 2008/0247599 A1.
A further method for extracting objects from an image data stream is known from US 2007/0250898 A1.
In US 2008/0240496 A1, a further method is known for analyzing image data streams, wherein superimposed objects are combined to form attributes.
In German patent document DE 10 2011 006 216 A1, a method is disclosed for the detection of dividing lines imaged on the road. By means of electromagnetic waves, the road surface is scanned in the direction of the vehicle width.
German patent document DE 10 2013 223 367 A1 discloses a method and a device for determining a road covering by way of a vehicle camera system. At least one image of a vehicle environment is taken by the vehicle camera system. This image is analyzed in order to detect evidence of precipitation and/or the presence of a road covering when the vehicle having the vehicle camera system or another vehicle drives over the road. The result of the determination of the road covering or of the coefficient of friction estimate derived therefrom can be outputted as a driver assistance function, a vehicle control function or also as information to a driver.
From European patent document EP 1 997 366 A1, an agricultural harvesting machine is known which has a foreign-body detection system, wherein foreign bodies are detected by a metal detection device.
In German patent document DE 197 38 007 C1, a method is described for the detection of the success of decontamination exercises. In this case, a contamination is simulated by way of a fluorescence-dye-containing oil film. After the removal of the oil film, the corresponding area is irradiated by fluorescence-stimulating light, so that residues of the oil can be easily and reliably determined.
The above-explained state of the art illustrates, on the one hand, that the contamination of a driving route or of a road by means of media, particularly oil, presents a considerable danger to the traffic that follows. In addition, the loss of certain media (gasoline, vehicle parts) may point to a danger situation at the motor vehicle that has lost the medium.
The inventors of the present invention recognized that there is a considerable need for automatically recognizing and evaluating such a loss of media.
The invention is therefore based on the object of creating a process for examining a loss of media of a motor vehicle as well as a motor vehicle and a system for implementing such a process, by which a loss of media at the motor vehicle can be reliably detected.
This and other objects are achieved by the process for examining the loss of media in accordance with embodiments of the invention.
In the case of the process for examining a loss of media of a motor vehicle according to the invention, by way of a first scanning device arranged on a motor vehicle, a route in the area in front of a motor vehicle that is driving in the travel direction and is to be monitored, and by way of a second scanning device arranged on a motor vehicle, the route behind the motor vehicle to be monitored, is scanned, wherein, when scanning the driving route, at least a forward and a rearward image are acquired, and the forward and rearward images are compared for detecting a medium lost by the motor vehicle to be monitored.
By way of the process according to the invention, the route, along which a motor vehicle to be monitored, is moving in the travel direction, is therefore scanned in the front in the travel direction and in the rear in the driving direction with respect to the motor vehicle by use of a scanning device, so that, via the thus acquired forward and rearward images, a loss of a medium can be detected. This loss is illustrated in the rearward image, but not in the forward image.
A scanning device in the context of the present invention is any device by which a two-dimensional or three-dimensional image of a driving route can be acquired. Such scanning devices are particularly an optical camera, an infrared camera, a laser scanner, a running-time camera, a stereo camera.
In order to permit a continuous monitoring of a media loss, forward and rearward images are taken at regular intervals, wherein the time interval can be adapted corresponding to the driving speed of the motor vehicle to be monitored. As a result a plurality of images are present, wherein preferably a forward image and a rearward image are assigned to one another in pairs respectively. The assignment can take place, for example, by use of a time stamp and/or location stamp, images with essentially the same location stamp being assigned to one another. When a time stamp is used, the driving speed of the motor vehicle or the speed of the corresponding traffic and the thereby covered path between the scanning of the forward image and the scanning of the rearward image are to be taken into account. The assignment of the images may also take place as an alternative to or in connection with a characteristics analysis of the images, wherein certain specific characteristics are extracted from the respective images, and the images are assigned to one another such that the largest number of these specific characteristics are contained in the two mutually assigned images (forward image and rearward image).
Such an analysis of characteristics may also be used for causing the forward and the rearward image respectively to mutually coincide. The respectively mutually assigned forward and rearward image, as a rule, do not exactly contain the same detail of the route. The forward and the rearward image are therefore preferably caused to coincide such that the corresponding specific characteristics are mutually superimposed, in order to then compare the two images.
The two images (forward image and rearward image) may also deviate from one another in the resolution, in the contrast, in the color representation and/or in the perspective. It is therefore useful to mutually adapt the images. If scanning devices, which are provided on the same motor vehicle, are used for acquiring the forward and rearward images, the characteristics of these scanning devices, such as the viewing direction, the focus, the resolution, are known, as a rule, so that the corresponding images can be adapted to one another by means of these known characteristics. If the scanning device has a zoom lens, the focus can be changed. The focus can be indicated in an angle range or at an imaging scale. However, if the scanning devices are arranged on different vehicles, it is probable that different types of scanning devices are used, of which, on the one hand, not all characteristics, such as the viewing direction or focus, are known or are not known with the same accuracy. In addition, the quality of the images, which are acquired by means of different types of scanning devices, may differ considerably. In such a situation, it is then useful to analyze the two images, in which case, also here, an analysis of characteristics may again be carried out or reused, in order to determine and mutually adapt the resolution, the contrast, the color representation and/or the perspective. This adaptation and/or alignment of the images can also be supported by use of acquired geographical coordinates assigned to the images.
The comparison of the two images preferably takes place by producing a differential image, the differential image showing all objects that are contained in only one of the two images. These objects are analyzed according to predefined rules. These rules are, for example:                Determination of a number of characteristics on a photo raster of both images;        determination of the coordinates (for example, in the center of the characteristics) of both images;        comparison of images with respect to the number of characteristics;        area determination of the new characteristics;        determination of the light reflection of the characteristics for recognizing the medium;        storing the identified old and new characteristics with the coordinate and detected time.        
The analysis of the objects can take place by use of the differential image and/or by use of the rearward image.
The analysis of the objects takes place, for example, by way of a shape analysis and/or a spectral analysis.
Several rearward images, which each show the object to be analyzed, can also be analyzed jointly via triangulation and/or characteristics analysis, so that a three-dimensional description of the surface of the object is produced. This corresponds to a stereo camera, in the case of which, instead of two cameras, only one camera is used, by which the images can be taken with a time offset.
The forward and rearward images can be taken by at least two scanning devices, which are arranged on different motor vehicles. These scanning devices may be arranged on a motor vehicle driving in front of the motor vehicle to be monitored as well as on a motor vehicle driving behind the motor vehicle to be monitored. However, one scanning device may be arranged on the motor vehicle to be monitored and another scanning device may be arranged on motor vehicle driving ahead or following. The images are preferably forwarded to a server, on which they are compared. As an alternative, it is also contemplated to exchange the images by way of a car-to-car communication between the motor vehicles and carry out the comparison of the images in a control device of one of the motor vehicles.
When a predefined medium is detected, one of the following actions can be carried out:                the vehicle driver of the monitored vehicle will be informed;        a public authority, such as the police or the Road Traffic Department will be informed;        traffic participants will be informed by means of car-to-car communication and/or light signals and/or honking.        
The motor vehicle according to the invention has at least a front scanning device and a rear scanning device for the scanning of a route, and a control device. The control device is designed for implementing one of the above-explained processes.
A system for implementing one of the above-explained processes comprises at least two scanning devices, which are arranged on a motor vehicle, the motor vehicle having a data connection to a server situated outside the motor vehicle, which server compares the forward and rearward images. The scanning devices may be arranged on the same motor vehicle or on different motor vehicles.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.